Malicious PDF — malware analysis report

Static analysis result for SHA-256 594deaa78f2b5292…

MALICIOUS

PDF

104.1 KB Created: 2021-06-28 02:21:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0b3c3fab32f7c79fb287576eaed76bd3 SHA-1: 1a4638e7ec3b5811ac925363724113e113404005 SHA-256: 594deaa78f2b5292eb35c2296981445c534c7c512d09b131d5c9976f5d34445b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, a common tactic for SEO poisoning and phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b962360a994---6050892722.pdf
    • http://harryreichert.de/uploaded_pics/News/file/nubomebipazitabikase.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/e8be9daa6ae9483391d522577b01078a/nutusimoruxamironigezi.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/924b130443803c25471d0543797dd43e/jibatokuvavivikurudavexu.pdf
    • http://adabaskimerkezi.com/upload/file/wejuzuvexik.pdf
    • http://guides2alpes.fr/uploads/file/lelirixapoziwikowoxuvu.pdf
    • https://anjingliar2.com/contents//files/34173647233.pdf
    • http://axiomestates.com/userfiles/file/vafuvomuzodiru.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/1dcaa26eccfde9f156409511c7b3f745/46968722542.pdf
    • http://bocghebinhduong.com/media/ftp/file/senefuni.pdf
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/65464309700.pdf
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/tumabimiweluxufedare.pdf
    • http://allamericannursing.com/userfiles/file/78665750626.pdf
    • http://peeweeslearningcenter.org/clients/5/54/545fcf94abc6bccf175f3035c740e6d3/File/wonufivadore.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090f46a5052a---vuxiwigamibuza.pdf
    • http://www.zywawiara.pl/pliki/vobewarenodanuf.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bbae4ee9c16---65933822963.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d928ae28c5---rujezuvajakemovidoduluw.pdf
    • https://peilimineko.com/userfiles/file/binuxesizaribepurawe.pdf
    • https://cristalensi.com/public/File/423924373.pdf
    • https://ikitellirezistans.com/upload/files/13795933974.pdf
    • http://wooshin.kr/uploaded/file/165593165460a92c6830c82.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=manual+of+clinical+anesthesiology+2nd+edition
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001338e.bin
1811f59a0bd9ae0e820f2af6950f02d7fc45112e8246bced0af2d435101c04fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x1338E 17656 bytes
font_01_sfnt_off00016171.bin
7c34a2e2f3015f44f372ecca75bf61d0fe4e952e53b7e13d96240f8a375b8ebc
pdf-font-stream PDF embedded font (sfnt) at offset 0x16171 10980 bytes
font_02_sfnt_off00017acb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17ACB 16792 bytes